The publication WO 01/01086 A1 discloses a method for compressibility compensation in the case of mass flow measurement in a Coriolis mass flow meter. In such case, a mass flow measurement is performed in two different modes, of which one is a bending oscillation mode and another a radial mode. The mass flow values ascertained by means of these two modes are compared. This is, however, a problematic approach, because the radial mode oscillations are significantly dependent on the flow profile and the static pressure. Additionally, more than the usual two sensors are required, in order to be able to register both bending oscillations as well as also radial mode oscillations. Equally, a more complex exciter structure is required.